Steam-heating system.



J. G. MIDGLEY.

STEAM HEATING SYSTEM.

APPLICATION FILED PBB.24, 1913.

1,081,509. Patented 1160.16, 1913.

JOHN Gr. MIDGLEY, E SALT LAKE C" UTAH.

'STEAM-@EATING SYSTEM.

Epeccation of Letters Patent.

Patented Bee. illu, ilt.

application led February-2e, 1913. Serial No. 750,220.

and usetul Improvements in Steam-Heating Systems, of which fthe following is .a specication.

My invention relates to .steam heating ap oi' pipes are ,employed,-one a radiator supply system, and .fthepot'her a return system from the radiators to the generator.

parntus of the cla-.SS in which two systemslln carrying out my invention l provide 'the generator and radiators with a system o-isli-pply .and neturn pipes and equip each radiator with a valve for passing air and water of condensation to the return system and preventing the passage oi steam thereto, and in the return system ll provide a separator from which air passes to the atmosphere, 'while the water of condensation ,1n the return system passes back to the generator. rlhe supply main is provided with "fone or more pipes -w-hich receive drip or wa'- Such systems, 'known as gravity systems, may beoperated under either high or low pressure or under vapor .or atmospheric pressure in4 the return system, or by vacuum in the returngsystem. My improvements are, however, preferably embodied in what is known as a low pressure gravity return system in which there is a dierential of pressure inf the two pipe systems, the radiators fleeing supplied with steam under low pressure and the air and water of condensation'from the radiators being passed through suitablev valves which prevent the passage or steam.'V ln such systems while eoient means have.

been provided for withdrawing air and water of condensation om ythe radiators, dif-- iculties have been .experienced in properly separating the air and water in the return system vand in returning the waiter of .con-

densation to the generator. A rise in pres-f sure in the 4generator .often causes water toA pass from the 'generator` into the return pipes destroying the low lpressure therein and preventing the radiators from being properly emptied of air and water so that they do not receive sufficient steam to heat them. It is highly ydesirable that there should be a constant di-erential of pressure in the supply and -return systems in order that the air and water of condensation may be most electively withdrawn fromlthe radiators and I purposely provide for such a condition, but I- also provide means whereby such diiierential of pressure may be maintained under all normal conditions, the low pressure in the return system being a1- ators maybe properly withdrawn and separated, and the water of condensation being .delivered -to the generator no matter what may be the pressure therein or to what extent the water may oscillate.

ways such that'the air and water from thera -i ter of condensation therein 'and return it to the generator, and means is provided of the `kind shown in Letters Patent or" the United States No. .963,613 granted lto me on July 5, 519,10, for promoting the new or" water under dierent pressures and temperatures from different parts oat the .system to the generator.

ln m patent just mentioned, means is shown or causing the water under various pressures and temperatures trom dilierent parts 4of the system to so dow toward the generator that any tendency of such returning water to pass back in the return system lis prevented. Such apparatus operated satisfactorily under some conditions, i. e., when :the pressure in the generator is relatively low, or when the differential of pressure in the two systems is not large, but when the pressure is considerable in the generator or in the supply system, or a great differential of pressure inthe two systems exists the apparatus shown in my patent will not produce the desired results. l have now however provided means whereby the rise of water in the return s stem to an injurious extent is prevented un er all pres'- sures and condition. l do this by interposing :between the separator and the generator and above the water line in the generator `means which are normally open to allow the passage of water to the generator when the pressure therein is low or normal but which closes lwhen thev pressure unduly rises when the dilierential in pressure inthe two systems is great, or 4when oscillations in the generator are such as to tend to cause water to pass fromthe generator 'tothe return system'. 'I have also provided the system with what I call a sta/tic head which" is connected with the separator and has in its upper orn tion a' valve which permits air to pass om the system but prevents it from entering it and when the pressure in the generator or in the return system is such that communi- .cation is cut ofi' between the separator and the generator and water of condensation rises in the return system to such an exten-t as to form a static head, then said static hea'd so operates as to open communication between the separator and the generator and permit water to How freely from the return system to the generator.

In the accompanying drawings I have shown my improvements embodied in a low pressure gravity return steam heating apparatus in which separate supply and return pipes are employed and in which a differential of pressure is maintained between the two systems, air being allowed to escape but prevented from entering the system, and the air and water of condensation being separated in a tank employed for this purpose. Some features of my invention, however, may be embodied in other systems operat ing under relatively high pressure, under vacuum, or under vapor or air pressure.

AFigure l is a diagram of a steam heating system embodying my improvements in the preferred way. Fig. 2 is a. detail view in section illustrating a device which I may employ for closing communication between the separator and the generator.`

, The radiators A are connected with the generator B by mea-ns of a supply system C.v

Eachl radiator is provided at the bottom with a valve which permits air and water of condensation to pass from the radiators, but prevents jthe passage of steam therethrough. Such valves are well known in this art and each of such valves communicates with a return system E which connects with a separator F of well known construction. From the separator'rises a pipe G having'at its upper end or in itsupper portion a valve H which' under normal conditions permits the passage of air from the separator to the atmosphere butprevents the entrance of air to the return system.

drip pipe I conveys water of condensation in the supply system to the generator and a pipe J conveys water from the separator to the generator. These pipes I and J extend into a return section'K ofthe kind shown in my 'patent before m'entioned and they cause the streams of water, which are of ditferenttemperatures and under different pressures, to flow in parallel streams for a time before mingling in such way, as de-` scribed in my before mentioned patent, as tb prevent the water in one part'of the return system fromrising in another part thereof when the differential of pressure in the two Vsystems, would otherwise cause it. The return section K is located below the water line in the generator as mentioned in my patent before referred to. Such apparatus operates under some conditioner-as when acentos the generator pressure is low or the diferential is not great, to cause the water to pass freely from the return system to the generator, but in order to render the apparatus eiicient under all conditions I interpose between the separator and the generator means located vabove the water line in the generator andalso in the return pipe J which is normally open to allow water to pass from the return system to the generator and which permits the apparatus' indicated at 'K to operate in the manner before described under some conditions but which will, when the pressure in the generator rises or the differential of pressure in the two systems varies, close communication between the separator and the generator and thus prevent water from passing from the generator into the return system. Preferably the device L used for this purpose is of the kind shown in Fig. 2. It comprises a casing l connected at l with the separator and at Z2 withv the pipe J. Within the casing is a float M normally resting on a support m and havinga't its upper end 'a valve m which lwhen the float rises sufficiently is seated at m2, As before stated the valve m is normally open and allows the apparatus' K to operate under normal conditions. If, however, the pressure in the generator increases, or the differential in the two systems is such -as to cause water to risel or tend to rise through the pipe J to the return system, or to the separator, the float M will rise-and cause the valve to close communication be- -tween the pipe J and thereturn system. It. is evident that no water is normally contained in the casing Z and hence the valve m is normally open.` Said valve m is ylocated above the.'water level of the generator and is also located above the normal water level in the return pipe J. If water rises in the casing the float will' rise and close the valve before any water can reach the valve seat and the more the water' rises and the greater the pressure below the float the more secure will the closure be. By this apparatus it is very clear that it is impossible for the water from the boiler to backl water of condensationl to pass itfreely. and.

that the normal level of water in the pipe J is at the same elevation as the water in Ythe boiler. The valve m operates only under abnormal conditions.

no water can vse oscillations have n o injurious effect and the valve remains tightly closed even when the i generator' pressure is very great and the oscillations are very pronounced. The devices shown in Fig, 2 are simple and eiiicient but others may4 be used for the Same purose.

lt will thus be seen that have provided a steam heating system in which .a diier, ential of pressure may be obtained, this differential of pressure being produced in the return s stem by the ,downwand iow of water o condensationto the generator, by.

the passage of air out of the system and by the vaporization of the water ofcondensation which passes from the radiators Under normal conditions water does not rise in the static head pipe G, but when the pressure in the generator is such as to close the valve at L, or the differential in pressure is such as todo this, the Waller of condensation passing into the separator F rises and fills the pipe G and is forced up into it by the pressure 4of steam or vapor,

under these abnormal conditions, contained in the return system. Water will continue to rise in the pipe G as long as the boilerl pressure is excessive and .holds the valve at L closed, but when the water in the pipe G has risen to a suiicient extent it will- .overcome the/boiler pressure and cause the valve at L to open so that water may pass from the se aratfr to the generator, the sta-tic head owe.er being maintained during these abnormal conditions.1 As soon, however, as the boiler pressure is reduced, water will fall in the pipe J and the water level in the static head pipe G will be lowered until when normal conditions are assumedl there will be no water in the pipe G but air may freely pass through this pipe, While the Water of condensation passing from the return pipes to the separator may pass. by the valve at L and through the pipe J to the generator. The water rising inthe static head pipe is, of lcou-rse, below the boiling point and does not-vaporize'at the top of' such column .of water, hence.v there is no tendency for 1t to rlse to such an extent aS to overiow.

It will thus be seen that I have provided a system in which a differential of pressure;

is maintained under normal conditions and the 'devices K ordinarily operate eiciently to prevent water from tpassing from the 4,geul erator to the return systems, but when the generator pressure increases beyond the power of the devices K, or the dierential in pressure is tooy great, the otherdevices which I have described operate with absolute certainty to prevent at any time the rise of water lroml the generator into the return system, and I have also provided means whereby when, water is prevented from flowing from the return system to the boiler, it forms a static column which, when it reaches proper elevation, opens communicationbetween the return system and the generator permitting water of condensation to ow back to the generator in the normal way, such devices being sor constructed and arranged that when the generator pressure falls, the static column also falls and the static pipe is finally emptied and then becOmBS a Ventilating pipe for the return system,

e I claim as my invention l, A steam heating system, comprising radiators, a generator, a supply system connecting .the generator with the radiators, a

separate retii'rn system from the radiators tothe generator, valves at the bottom of the radiators which permit air and waterof- ,COlldensatQn to pass to the return system but which prevent ,the passage of Steam thereto, a val-ve easngiconneoted in the reftupn system and located above the normal Water level in the return pipeand a valve device .in Smid casing located above the normal water lille in. the return system for closing .communication above said water line between the return system and the generator whenever water tends to pass from the generator to the,l return system by reason of .an increased essure in the enerator, or

va diderential o pressures in t ge system.

2, A Steam heating system, comprising radiators, a generator, a supply system con' `necting the radiators and generator, a separate return system from the radiators tothe generator, -yalves interposed between thebottorn of :the radiators and the return system for permitting air and water of condensation to passto the return system ybut which prevent the passage of steam thereto, asepa rator into which the air and water of condensation passes, means for conveying `the separated airto the atmosphere, .devices` for ,preventing air from. passing from the atmosphene to the return system, a connection between, the .Separator and the generator, a valve casing in said connection between the separator andthe generator, and a valve .de-

f vice in said casing located abone the nominal water level in the `return system for closing communication above said water -l-'me between the separator and generatorwhenever water tends ,to pass strom the .generator to the se arator.

3. vsteam ing system, comprising ra preventing the entrance of air to the sepaf rator, a pipe connection between the separator and the generator, a valve casing 1n said pipe connection located below the separator and above the normal water level in thereturn system and a valve in saidcasing for closing communication above saidy water line between the separator and generator whenever water tends to pass from the generator to the separator.

4. A steam heating system, comprising radiators, a generator, a supply system connecting the radiators with the generator, ai

separate return system from the radiators to the generator, valves interposed between the bottom of the radiators and the return system for permitting air and water to pass from the'radiators to the return system but which prevent the 'passage of steam thereto',-

a separator in the return system to which air and water are delivered, means for conducting air from the separator to the atmosphere, devices for preventing the entrance of air/to the return system, a connection between the separator and thegenerator and a float valve interposed in such connection locatedabove the normal water level in the return system and which closes when' water lpasses from the generator toward the separator beforesuch water reaches the point of closure, y

5. A steam heating system, comprising radiators, a generator, a supply'system connecting the radiators with the generator, a separate return system from the radiators `to the generator, valrves interposed between the bottom of the radiators and the return system for permittin air and waterv of condensation to pass rom the radiators to the return system but which prevent the passage of steam thereto, a separator in the return system where air and water of con.- densation are separated, connections between the separator and the. generator whereby.

water of condensation passes back tothe generator, a valve device located above the normal water level in the return system for closing communication above said water line betweenthe enerator and the separator when the water rom the generator tends to pass to the separator and a pipe connected with the separator provided withy a valve which permits air toA 'pass ,from the sepa- Loana-sa rator to the atmosphere but prevents the entrance of air thereto and which vpipe is adapted to receive a head of water from the return system which Awhen sufiicient opens communication between the separator and the generator. y

6. A steam heating system, comprising radiators, a generator, a supply system connectingl the radiators with the generator, a separate return system from the radiators to the generator, valves interposed between the return system and the bottom of the radiators for permitting air and water of condensation to pass from the radiators to the return system but .which prevent the passage of steam thereto, means for conducting air from the return system to the atmosphere and for preventing the entrance of air thereto, means whereby separate streams of water returning to the generator from dierent parts of the system are caused to flow substantially parallel with one another before mingling and entering the generator for overcoming and equalizing the differential of pressureexisting in the system and preventing the flow of water from one part of the system back into another part thereof, and a valve device located above the normal water level in the return `system for closing communication above said water level between the generator and the return system whenever the pressure in the generator rises to a considerable extent or when the-differential of pressure in the supply and'return systems is such as to tend to cause water to pass from the gen- *erator into the return system.

y 7. A steam' heating system, comprising radiators, a generator, a supply system connecting the generator with the radiators, a separate return system from the radiators to lthe generator, valves at the bottoms of the radiators through which air and water of condensation pass from the radiators to the return pipes, and a float valve in thereturn system located above the normal water level Vin the return system for closing communication above said water level between the return system and the generator whenever water tends to pass from the generator to the return system andbefore water rises to said point of closure. v

8. A i steam heating system, comprising radiators, a generator, a supply system connecting the generator with the radiators, a separate return system from the radiators tothe generator, valves at the bottom of the radiatorswhich permit air and water of condensation to pass to the return .sys-

tem but which prevent the passage of steam thereto, a pipe connected with the return system through which air passes therefrom to the atmosphere and in which a static head may be formed 'by water of condensation from the return system, means for preventing the admission of air from the atmosphere to said pipe, a valve casing connected with the return system and with the generator located above the normal water level in the return system, and a valve device in said casingv for closing communication above said water line between the return system and the generator whenever water tends to pass from the generator to the return system by reason of an increased pressure` in the generator, a differential of pressure in the system, or the oscillations of water in the generator, said closing means being in communication with said static head whereby when said static head reaches a certain elevation said closing means may be opened thereby.

9. A steam heating system, comprising radiators, a generator, a supply system connecting the generator with the radiators, a separate return system from the radiators to the generator, valves at the bottom of the radiators which permit air and water of condensation to pass to the return system but which prevent the passage of steam thereto, means for conveying drip water from the supply system to the generator, a valve in the return system located above the normal water level in the return system which is normally open but which closes communication yabove said water line between the return system and the generator whenever water tends to pass from the generator to the return system by reason of an increased pressure, in the generator.

l0. A steam heating system, comprising radiators, a generator, a supply system connecting the generator with the radiators, a separate ret-urn system from the radiators to the generator, valves at the bottom ofthe radiators which permit air and water of condensation to pass to the return system but which prevent the passage of steam thereto, a separator into which the air and water yof condensation passes, means for conveying the separated air to the atmosphere, devices for preventing air from passing from the atmosphere vto the return system, a connection between the separator and the generator, a normally open valve interposed in saidconnection and located above the normal water level in the return system for closing communication above said water line between the separator and generator whenever water tends to pass from the generator to the separator but which under normal conditions is open and permits water of condensation to flow from the separator to the generator.

In testimony whereof, I have hereunto subscribed my name.

J. H. GLENN, Tiros. M. W. 

